Basically 800 years ago, when xie lian was still a mortal, he saved hua cheng from dying. Huacheng was severely bullied and had no family that we know of, he also was extremely insecure because of the bullying and became kinda suicidal. After xielian ascended, hua cheng devoted his life to him because of the time he saved his life. Xielian also said hua cheng to live on for him if he has no reason to live. San lang dosent only like him, he is devoted to him, he is xia lian's most devoted follower. Sorry if this is confusing.

Someone who's read the novel.
Can you explain the story behind when and how did San lang know Xianle. First times Xianle met Sang lang already likes him.
Thank you so much.